Debian Security Advisory

DLA-2910-1 ldns -- LTS security update

Date Reported:
04 Feb 2022
Affected Packages:
Security database references:
In Mitre's CVE dictionary: CVE-2020-19860, CVE-2020-19861, CVE-2017-1000231, CVE-2017-1000232.
More information:

It was discovered that there were four issues in ldns, a library used in Domain Name System (DNS) related programs:

  • CVE-2020-19860

    When ldns version 1.7.1 verifies a zone file, the ldns_rr_new_frm_str_internal function has a heap out of bounds read vulnerability. An attacker can leak information on the heap by constructing a zone file payload.

  • CVE-2020-19861

    When a zone file in ldns 1.7.1 is parsed, the function ldns_nsec3_salt_data is too trusted for the length value obtained from the zone file. When the memcpy is copied, the 0xfe - ldns_rdf_size(salt_rdf) byte data can be copied, causing heap overflow information leakage.

  • CVE-2017-1000231

    A double-free vulnerability in parse.c in ldns 1.7.0 have unspecified impact and attack vectors.

  • CVE-2017-1000232

    A double-free vulnerability in str2host.c in ldns 1.7.0 have unspecified impact and attack vectors.

For Debian 9 Stretch, these four problems have been fixed in version 1.7.0-1+deb9u1.

We recommend that you upgrade your ldns packages.

Further information about Debian LTS security advisories, how to apply these updates to your system and frequently asked questions can be found at: